Conventionally, from the viewpoint of improving the safety of vehicles, studies have been conducted to improve performance of tires, such as braking performance and driving performance, not only on dry road surfaces but also on other different road surfaces, such as wet road surfaces and icy and snowy road surfaces.
For example, in order to improve performance of a tire on an icy and snowy road, JP 11-060770 A and JP 2001-233993 A (PTL 1-2) each disclose a tire that uses a rubber composition containing a fiber including a resin for the tread, where elongated air bubbles coated by this resin are formed after vulcanization so that they can function as drainage channels as the tread wears to thereby provide improved drainage performance. Attempts have also been made to provide even better drainage performance by using a hydrophilic material as this resin and making use of the affinity for water.